No, the key take-home points from the Long Term Capital Management fiasco are:

The market can remain irrational longer than you can remain solvent.

Don't bet your entire business that you're the smartest guy on the block.

Don't bet your entire business on any single transaction, particularly when that transaction does not keep the two first bullets firmly in mind.

Of course, none of this should have been in any way novel or surprising, and the fact that humanity regularly has to re-learn such simple matters of common prudence does not auger well for our collective cognitive prowess.